Arachnida

1 9.4

A group of animals like spiders and scorpions that have eight legs and no antennae or wings

noun
/əˈræknɪdə/

Specialized

: arácnido

Scientists have discovered a new species within the Arachnida class inhabiting the rainforest canopy.

Examples

The Arachnida are fascinating.
The biology textbook includes a detailed chapter on Arachnida and their life cycles.
Unlike insects, members of the Arachnida have eight legs and lack antennae.
Look at that Arachnida!
The class Arachnida includes various species, such as spiders and scorpions, that are characterized by having eight legs.
Researchers study the class Arachnida to understand the role of spiders and ticks in the ecosystem.
Many creatures in the class Arachnida, like mites and scorpions, play important roles in pest control.

Synonyms

arachnid

vsArachnida

11 6.8

An animal with eight legs like a spider or scorpion

focuses on being a large class defined by no wings or antennae

arachnoid

vsArachnida

1 9.6

An animal like a spider with eight legs, not an insect

refers to the whole class and stresses absence of wings or antennae

Surface Forms

Arachnida singular

Arachnidas plural

Morphology

Arachnida = arachnid (semi-transparent) = arachnid + a

Formed from the common term 'arachnid' with a specialized taxonomic suffix '-a' to denote the biological class, which is understandable but a domain-specific formation.

Etymology

The word Arachnida comes from the Greek root arachne, which means 'spider'. So Arachnida names the animal group that includes spiders, scorpions, ticks, and mites—think 'spider' to remember these eight-legged animals.